1. General Results, most used to calculate the result A name "api.openai.com" is subdomain, public suffix is ".com", top-level-domain is ".com", top-level-domain-type is "generic", tld-manager is "VeriSign Global Registry Services", num .com-domains preloaded: 86299 (complete: 221801) A Good: All ip addresses are public addresses A Good: Minimal 2 ip addresses per domain name found: api.openai.com has 2 different ip addresses (authoritative). Warning: No ipv6 address found. Ipv6 is the future with a lot of new features. So every domain name should have an ipv6 address. See https://en.wikipedia.org/wiki/IPv6: api.openai.com has no ipv6 address. A Good: No asked Authoritative Name Server had a timeout A DNS: "Name Error" means: No www-dns-entry defined. This isn't a problem A Good: No cookie sent via http. HSTS-Preload-Status: unknown. Domain never included in the Preload-list. Check https://hstspreload.org/ to learn some basics about the Google-Preload-List. A Good: Some urls with http status 200/404 have a complete Content-Type header (MediaType / MediaSubType + correct charset):0 complete Content-Type - header (3 urls) https://api.openai.com/ 104.18.6.192 Url with incomplete Content-Type - header - missing charset https://api.openai.com/ 104.18.7.192 Url with incomplete Content-Type - header - missing charset https://api.openai.com/.well-known/acme-challenge/check-your-website-dot-server-daten-dot-de Url with incomplete Content-Type - header - missing charset A http://api.openai.com/ 104.18.6.192 https://api.openai.com/ Correct redirect http - https with the same domain name A http://api.openai.com/ 104.18.7.192 https://api.openai.com/ Correct redirect http - https with the same domain name B Warning: HSTS max-age is too short - minimum 31536000 = 365 days required, 15724800 seconds = 182 days found C Error - no version with Http-Status 200 H Fatal error: No https - result with http-status 200, no encryption M https://api.openai.com/ 104.18.6.192 Misconfiguration - main pages should never send http status 400 - 499 M https://api.openai.com/ 104.18.7.192 Misconfiguration - main pages should never send http status 400 - 499 P https://104.18.6.192/ 104.18.6.192 Error creating a TLS-Connection: No more details available. P https://104.18.7.192/ 104.18.7.192 Error creating a TLS-Connection: No more details available. A Good: More then one ip address per domain name found, checking all ip addresses the same http status and the same certificate found: Domain api.openai.com, 2 ip addresses. Info: Checking the ip addresses of that domain name not exact one certificate found. So it's impossible to check if that domain requires Server Name Indication (SNI).: Domain api.openai.com, 2 ip addresses. B No _mta-sts TXT record found (mta-sts: Mail Transfer Agent Strict Transport Security - see RFC 8461). Read the result of server-daten.de (Url-Checks, Comments, Connections and DomainServiceRecords) to see a complete definition. Domainname: _mta-sts.api.openai.com 2. Header-Checks (alpha, started 2022-10-23, may be buggy / incomplete) F api.openai.com 104.18.6.192 Content-Security-Policy Critical: Missing Header: F api.openai.com 104.18.6.192 X-Content-Type-Options Critical: Missing Header: F api.openai.com 104.18.6.192 Referrer-Policy Critical: Missing Header: F api.openai.com 104.18.6.192 Permissions-Policy Critical: Missing Header: F api.openai.com 104.18.7.192 Content-Security-Policy Critical: Missing Header: F api.openai.com 104.18.7.192 X-Content-Type-Options Critical: Missing Header: F api.openai.com 104.18.7.192 Referrer-Policy Critical: Missing Header: F api.openai.com 104.18.7.192 Permissions-Policy Critical: Missing Header: 3. DNS- and NameServer - Checks A Info:: 8 Root-climbing DNS Queries required to find all IPv4- and IPv6-Addresses of 4 Name Servers. A Info:: 8 Queries complete, 8 with IPv6, 0 with IPv4. A Good: All DNS Queries done via IPv6. A Good: Some ip addresses of name servers found with the minimum of two DNS Queries. One to find the TLD-Zone, one to ask the TLD-Zone.ns1-01.azure-dns.com (13.107.236.1, 2603:1061:0:700::1), ns2-01.azure-dns.net (150.171.21.1, 2620:1ec:8ec:700::1), ns3-01.azure-dns.org (204.14.183.1, 2a01:111:4000:700::1), ns4-01.azure-dns.info (208.84.5.1, 2620:1ec:bda:700::1) A Good (1 - 3.0):: An average of 2.0 queries per domain name server required to find all ip addresses of all name servers. A Info:: 4 different Name Servers found: ns1-01.azure-dns.com, ns2-01.azure-dns.net, ns3-01.azure-dns.org, ns4-01.azure-dns.info, 4 Name Servers included in Delegation: ns1-01.azure-dns.com, ns2-01.azure-dns.net, ns3-01.azure-dns.org, ns4-01.azure-dns.info, 4 Name Servers included in 1 Zone definitions: ns1-01.azure-dns.com, ns2-01.azure-dns.net, ns3-01.azure-dns.org, ns4-01.azure-dns.info, 1 Name Servers listed in SOA.Primary: ns1-01.azure-dns.com. A Good: Only one SOA.Primary Name Server found.: ns1-01.azure-dns.com. A Good: SOA.Primary Name Server included in the delegation set.: ns1-01.azure-dns.com. A Good: Consistency between delegation and zone. The set of NS records served by the authoritative name servers must match those proposed for the delegation in the parent zone. Ordered list of name servers: ns1-01.azure-dns.com, ns2-01.azure-dns.net, ns3-01.azure-dns.org, ns4-01.azure-dns.info A Good: All Name Server Domain Names have a Public Suffix. A Good: All Name Server Domain Names ending with a Public Suffix have minimal one IPv4- or IPv6 address. A Good: All Name Server ip addresses are public. A Good: Minimal 2 different name servers (public suffix and public ip address) found: 4 different Name Servers found A Good: All name servers have ipv4- and ipv6-addresses.: 4 different Name Servers found A Good: Name servers with different Top Level Domains / Public Suffix List entries found: 4 Name Servers, 4 Top Level Domains: com, org, net, info A Good: Name Servers with different domain names found.: 4 different Domains found A Good: Name servers with different Country locations found: 4 Name Servers, 3 Countries: CA, IE, US A Info: Ipv4-Subnet-list: 4 Name Servers, 4 different subnets (first Byte): 13., 150., 204., 208., 4 different subnets (first two Bytes): 13.107., 150.171., 204.14., 208.84., 4 different subnets (first three Bytes): 13.107.236., 150.171.21., 204.14.183., 208.84.5. A Excellent: Every Name Server IPv4-address starts with an unique Byte. A Info: IPv6-Subnet-list: 4 Name Servers with IPv6, 3 different subnets (first block): 2603:, 2620:, 2a01:, 3 different subnets (first two blocks): 2603:1061:, 2620:01ec:, 2a01:0111:, 4 different subnets (first three blocks): 2603:1061:0000:, 2620:01ec:08ec:, 2620:01ec:0bda:, 2a01:0111:4000:, 4 different subnets (first four blocks): 2603:1061:0000:0700:, 2620:01ec:08ec:0700:, 2620:01ec:0bda:0700:, 2a01:0111:4000:0700: A Good: Name Server IPv6 addresses from different subnets found. A Good: Nameserver supports TCP connections: 8 good Nameserver A Good: Nameserver supports Echo Capitalization: 8 good Nameserver A Good: Nameserver supports EDNS with max. 512 Byte Udp payload, message is smaller: 8 good Nameserver A Good: Nameserver has passed 10 EDNS-Checks (OP100, FLAGS, V1, V1OP100, V1FLAGS, DNSSEC, V1DNSSEC, NSID, COOKIE, CLIENTSUBNET): 8 good Nameserver Nameserver doesn't pass all EDNS-Checks: ns1-01.azure-dns.com: OP100: no result. FLAGS: no result. V1: no result. V1OP100: no result. V1FLAGS: no result. DNSSEC: no result. V1DNSSEC: no result. NSID: no result. COOKIE: no result. CLIENTSUBNET: no result. A Good: All SOA have the same Serial Number A Good: CAA entries found, creating certificate is limited: amazon.com is allowed to create certificates A Good: CAA entries found, creating certificate is limited: digicert.com is allowed to create certificates A Good: CAA entries found, creating certificate is limited: godaddy.com is allowed to create certificates A Good: CAA entries found, creating certificate is limited: letsencrypt.org is allowed to create certificates A Good: CAA entries found, creating certificate is limited: pki.goog is allowed to create certificates A Good: CAA entries found, creating certificate is limited: sectigo.com is allowed to create certificates A Good: CAA entries found, creating certificate is limited: amazon.com is allowed to create wildcard-certificates A Good: CAA entries found, creating certificate is limited: digicert.com is allowed to create wildcard-certificates A Good: CAA entries found, creating certificate is limited: letsencrypt.org is allowed to create wildcard-certificates A Good: CAA entries found, creating certificate is limited: pki.goog is allowed to create wildcard-certificates A Good: CAA entries found, creating certificate is limited: sectigo.com is allowed to create wildcard-certificates 4. Content- and Performance-critical Checks A Good: All checks /.well-known/acme-challenge/random-filename without redirects answer with the expected http status 404 - Not Found. Creating a Letsencrypt certificate via http-01 challenge should work. If it doesn't work: Check your vHost configuration (apachectl -S, httpd -S, nginx -T). Every combination of port and ServerName / ServerAlias (Apache) or Server (Nginx) must be unique. Merge duplicated entries in one vHost. If you use an IIS, extensionless files must be allowed in the /.well-known/acme-challenge subdirectory. Create a web.config in that directory. Content: <configuration><system.webServer><staticContent><mimeMap fileExtension="." mimeType="text/plain" /></staticContent></system.webServer></configuration>. If you have a redirect http ⇒ https, that's ok, Letsencrypt follows such redirects to port 80 / 443 (same or other server). There must be a certificate. But the certificate may be expired, self signed or with a not matching domain name. Checking the validation file Letsencrypt ignores such certificate errors. Trouble creating a certificate? Use https://community.letsencrypt.org/ to ask. A Info: No img element found, no alt attribute checked A Good: Domainname is not on the "Specially Designated Nationals And Blocked Persons List" (SDN). That's an US-list of individuals and companies owned or controlled by, or acting for or on behalf of, targeted countries. It also lists individuals, groups, and entities, such as terrorists and narcotics traffickers designated under programs that are not country-specific. Collectively, such individuals and companies are called "Specially Designated Nationals" or "SDNs." Their assets are blocked and U.S. persons are generally prohibited from dealing with them. So if a domain name is on that list, it's impossible to create a Letsencrypt certificate with that domain name. Check the list manual - https://www.treasury.gov/resource-center/sanctions/sdn-list/pages/default.aspx https://api.openai.com/ 104.18.6.192 1.970 seconds Warning: 404 needs more then one second https://api.openai.com/ 104.18.7.192 1.623 seconds Warning: 404 needs more then one second https://api.openai.com/.well-known/acme-challenge/check-your-website-dot-server-daten-dot-de 1.653 seconds Warning: 404 needs more then one second A Duration: 88750 milliseconds, 88.750 seconds